Some susceptible patients will have recurrent issues with hyperpigmentation, and often the problem will be ongoing for many years unless treated. Surgical scars can become hyperpigmented (darker in colour) and stabilize so that the colour never returns to ‘normal’ unless actively treated. For example, see Figures 1, 2, and 3, showing stable darkened skin along the breast augmentation scar at 2 years and four years after surgery. Clearly, unless the pigment is treated, this problem is not likely to go away on its own.

Figure 1: Pre Op-Patient of mixed genetic heritage, Type III skin.

Figure 2 Four years Post Op Breast Augmentation

Figure 3 Scar hyperpigmentation four years after surgery. (Before Starting Treatment)

What is PIH?

PIH refers to the increased pigment (darkening) of the area around an scratch, cut, burn or other injury to the skin. Melanocytes are the skin cells responsible for making melanin, the substance that gives colour to the skin. Melanin is made through a chemical process that changes the amino acid tyrosine with the oxidative enzyme tyrosinase. The process is stimulated by the exposure of the skin to ultraviolet light (UV). Skin irritation alone is sufficient to cause the problem of PIH in susceptible individuals. Caution and medical supervision is necessary during treatment, since many of the treatments can cause more skin irritation, and thereby paradoxically induce even more PIH!

Who gets PIH?

PIH is mainly a problem for people of colour who are just slightly darker than the average white American or European. Although it is not painful, and it can be hidden with cosmetics, PIH is very annoying and can cause significant emotional distress.

Patients who have very light coloured skin, (natural) hair colour, irises (eye colour) almost never have this problem, in contrast to Asians, North American Indians, and other peoples of darker tinted skin. Patients suffer from the dyschromia or altered pigmentation following even the mildest of skin irritations or injuries. For example, people of colour who also like to cook, will often have some discolouration of their forearms, where they accidentally received trivial burns. The burn heals promptly, but the darkening of the skin at the site of injury can last for years afterwards. Even as insignificant an issue as a pimple can result in a dark spot on the face that lasts for months or years, creating a long lasting blemish that takes forever to clear up, very long after the original injury goes away. In fact, PIH is more of a problem for acne victims in persons of colour than the acne itself.

How can we treat PIH?

First, the physician has to sort out the cause of the problem. A thorough history and physical examination is usually sufficient to determine the aetiology of PIH, which can then be treated. The most effective treatments involve several components that must be customized to the patients’ situation. Usually this involves treatment of the underlying problem (for example, treating acne), then using medications to reduce the local manufacturing of melanin. Typical lightening preparations contain hydroquinone, kojic acid, retinoids such as tretinoin, azelaic acid, or niacinamides.

Successful management of PIH involves combination therapy. In addition to the medications mentioned, we often use phototherapy (fractionated laser therapy, flat beam laser treatments, or intense pulsed light treatments), chemical peels, and surgical depigmentation to improve the appearance of PIH. Combinations of these treatment modalities can significantly improve the appearance of this problem. As with many other genetically determined problems, we cannot cure the underlying problem, but we can manage it, thereby improving the quality of life for affected people.

Claudio DeLorenzi MD FRCS
Plastic Surgeon